Tank balls



A ril 20, 1965 K. L. ZIMMERMAN 3,178,729

TANK BALLS Original Filed July 6, 1960 INVENTOR KM. Z

a ilf'ORNEY United States Patent Ofiice 3,178,729 Patented Apr. 20, 19653,178,729 TANK BALLS Karl L. Zimmerman, Philadelphia, Pa., assiguor toWoodward Wanger Company, Philadelphia, Pa, a corporation of PennsylvaniaContinuation of application Ser. No. 41,206, July 6, 1960.

This application Aug. 7, 1962, Ser. No. 215,453 3 Claims. (Cl. 4--56)This invention relates to improvements in flexible, buoyant valves foruse in flush tanks and the like. The type of valve of the kind inquestion is commonly called a tank ball and will be referred to as suchhereinafter.

The principal object of the invention is to provide a tank ball havingmaximum seating or sealing ability and usable with any of the variousstandard sizes and types of flush valve seats.

This application is a continuation of my application Serial No. 41,206,filed July 6, 1960, and now abandoned.

The preferred structure for accomplishing the foregoing will beunderstood from the following description and drawings wherein:

FIGURE 1 is a cross sectional view of one form of tank ball embodyingthe invention; and

FIGURE 2 is a cross sectional View of another form of tank ballembodying the invention.

In FIGURES 1 and 2 the tank balls 1 and 2 are made from a flexiblematerial such as natural rubber. In FIG UREl the tank ball has a hollowupper part 3 and a hollow lower part 4 which are integral with oneanother and symmetrically disposed about the ball axis A. The joinderarea 5 between the upper and lower parts is formed with a channel 6. Thetop part 3 has a threaded insert by means of which the ball is attachedto the tank operating linkage. The tank-ball of FIGURE 2 has a hollowtop part 11 and a hollow bottom part 12. which are integral with oneanother and symmetrically disposed about the ball axis A-1. The joinderarea 13 has a channel 14 and the top part is provided with a threadedinsert 15.

Each of the tank balls 1 and 2 has a surface of revolution whichconstitutes the seating or sealing area. In the ball 1 the seating area16 extends around the bottom part 4, the upper limit of which is theterminus indicated by 20 and the lower limit of which is the terminusindicated by 21. In FIGURE 2 the seating area 22 extends around thebottom 12 and the upper limit being at the terminus 23 and the lowerlimit at the terminus 24.

As will be apparent, the seating area 16 of FIGURE 1 is a curved surfaceof revolution while the seating area 22 of FIGURE 2 is a plane surfaceof revolution. The orientation of the sealing area curve (distancebetween upper and lower termini) is important in obtaining theobjectives of the invention, namely, improved sealing characteristicsand universality of use. It is important that the length of the radiusof the surface be greater than one-half the diameter of the ball takenat the upper terminus and that the center of this radius be locatedabove the upper terminus either on or spaced from the axis A. Preferablythe radius should be at least 65% of the diameter taken at the upperseating terminus.

For example, in FIGURE 1 the curve of the surface 16 has a radius 25,the center 26 of which is spaced from the axis A. The length of theradius is greater than one-half the diameter 30 taken at the upperterminus 20 of the seating area.

By locating the center of the radius as mentioned the slope of the curvecan be flatter and more nearly normal to the axis of the ball. Thisminimizes the axial length of the ball while at the same time providingmaximum diameters for the seating area. This structure has particularadvantage in adapting the ball for use and those instances whereallowable ball travel (distance lifted oil the seat) is restricted, forexample, in the modern type minimum height flush tanks. Furthermore, thecurve orientation and particularly the larger diameters permit the tankball to be used with all standard sizes of tank seats. Another advantageis that the seating area is oriented so that it is particularly suitablefor use with the recently introduced China flush valve seats.

It is to be observed in FIGURE 1 that the portions of the ball outsidethe seating area 16 are formed by the radii 31 and 32. It will beunderstood, of course, that there may be a certain amount of overlappingbetween the curves formed by the radii 25, 31 and 32 in order to formthe entire contour of the lower part 4. With the above in mind, however,it will be understood that essentially the curve of the seating surface16 is formed by the radius 25.

In FIGURE 2 the radius 33 has its center at infinity and as such thelength of the radius is greater than onehalf the diameter 34. Also, thecenter of the radius is spaced from the axis A-1.

Another important factor in the construction of the ball is therelationship between the total length of the ball and the diameter takenat the upper terminus of the seating area. The length of the ball shouldbe between 50% and 70% of the terminus diameter. These limits are afunction of the minimum length of the ball (to suit for restrictedtravel) the maximum and minimum diameters of the seating area inrelation to the required volume (particularly in the lower part of theball) to allow the necessary buoyancy. In FIGURE 1 the length 40 is 60%of the diameter 30. The same relationship pertains between the length 35and the diameter 34 of the ball of FIGURE 2.

Another important factor is the axial distance between the upperterminus of the seating area and the lower end of the ball with relationto the upper seating area diameter. This axial distance should bebetween 25% and 33% of the diameter. In FIGURE 1 the distance 43 is 27%(which is the preferred length) of the diameter 30. In FIGURE 2 thedistance 44 is 27% of the diameter 34. The above-mentioned lengths arefunctions of the length and location of the seating curve radius and thelength of the diameter at the upper seating terminus.

With the above-described construction the center of gravity of the ballis located very close to the seating area. This has the distinct andimportant advantage of lending stability to the ball so as to enhanceits seating or sealing characteristics. It is preferred that the centerof gravity of the ball lie very close to the upper terminus of theseating area or in the plane containing the terminus. For example, inFIGURE 1 the plane P-1 normal to the axis A contains the upper terminus20 of the seating area. The plane P-Z normal to the axis A contains thecenter of gravity (C.G.) of the ball. These two planes are separated bythe distance 41 which is about 17% of the length 40. In FIGURE 2 theplane P-3 contains the upper terminus 23 and the plane P-4 contains thecenter of gravity (C.G.) and these two planes are separated by thedistance 42 which is about 17% of the length 35.

In connection with the location of the center of gravity, I have foundthat where the center of gravity does not lie within a plane containingthe upper terminus the ratio of the diameter of the upper seatingterminus to the length of the ball to distance between the center ofgravity and the upper terminus should be between 5 and 12. In FIGURE 1the ratio of the diameter 30 to 1. A tank' ball c :omprisingz v ahollow, flexible 'body' formed a'lower part, the parts being integralwith one another and jsymmetrically. arranged with respect to the axisof the ballgthe lower part' having an external seat ing area formed byacurved surface of revolution,

the center ofthe r-adius of the curve ofsaid surface being located abovethe upper terminus of the seat-- ing area and' being spaced fromsaidr-axis'and having a length greater than 65% of the diameter of thehall taken through the upper terminus of the seating area, f A 7 thetotal axial length of the ballr including said upper andlower'partsbeing between 50% and 70% of'said diameter,- e V v the axialdistance between said upper terminusand the A lower end' of the hallbeing' between 25% and 30% of said diameter, e

V and the center of gravity of the' ball'b eing located on;

V said'axis above 'said upper terminus. e

2. A tank ball comprising:

by an upper part and the total axial llength of the'ball including saidupper a hollow, flexible body'forrnedby an-upper part and I 'alowerpart,*the parts being integral with one-another and symmetricallyarranged 'with respect to the am's of the ball, the'jlower' part havingan. ex-

ternal seating area for med'by a curved; surface of revolution;

the center'of' the radius of the curveflofesaid sur-facel being locatedabove theupperterminusof theseat 5 ingarea and'being spaced fromesaidaxis'rand having a length greater than 65% of the diameter of: the iball taken through the upper terminusof the seating area, a

a a 4 e the total axial length of the ball including said upper 1 andlower parts being of said diameter,

the axial distance-between said upper terminus and the lower end of theball being 27% of said diameter;

and the center of gravity of; the ball being located on said; axis abovesaid upper terminus.

'3. A tank ball comprising: a

a hollow, flexible body formed by an upper part and a lower part, theparts' being integral with one another and symmetrically arranged withrespect to the; axis of the ball, the lower part having anexternalseating area forined by a curved surface of Q revolutio'n, V 1the center-of the radius "of the curve of said surface being locatedabove theupper terminus of the seat, ing area and being spaced "fromsaid axis and having a length greater than-% of the diameter of the balltakenthrough the upperter-ininusof the seating area;

and lowerparts being6 0% of said diameter,

' the axial distance between said upper terminus and the lower e d ofthe ball being 27% or 'said diameter, and the center of gravity ofthe.ball;b'eing located on said axis above said upper terminus with theaxial distance between the'center of' gravity andfthe upper terminusbeing 17% of said total-length.

e References Cited biy the Examiner UNITED STATES PATENTS "EDWARD v.BENI-IAM, Primary'Examinelr.

BRONAUGH, Examiner.

7/26 Shook" 4-57

1. A TANK BALL COMPRISING: A HOLLOW, FLEXIBLE BODY FORMED BY AN UPPERPART AND A LOWER PART, THE PARTS BEING INTEGRAL WITH ONE ANOTHER ANDSYMMETRICALLY ARRANGED WITH RESPECT TO THE AXIS OF THE BALL, THE LOWERPART HAVING AN EXTERNAL SEATING AREA FORMED BY A CURVED SURFACE OFREVOLUTION, THE CENTER OF THE RADIUS OF THE CURVE OF SAID SURFACE BEINGLOCATED ABOVE THE UPPER TERMINUS OF THE SEATING AREA AND BEING SPACEDFROM SAID AXIS AND HAVING A LENGTH GREATER THAN 65% OF THE DIAMETER OFTHE BALL TAKEN THROUGH THE UPPER TERMINUS OF THE SEATING AREA, THE TOTALAXIAL LENGTH OF THE BALL INCLUDING SAID UPPER AND LOWER PARTS BEINGBETWEEN 50% NAD 70% OF SAID DIAMETER, THE AXIAL DISTANCE BETWEEN SAIDUPPER TERMINUS AND THE LOWER END OF THE BALL BEING BETWEEN 25% AND 30%OF SAID DIAMETER, AND THE CENTER OF GRAVITY OF THE BALL BEING LOCATED ONSAID AXIS ABOVE SAID UPPER TERMINUS.